SQL Server performance with many concurrent, long-running queries

Question

I\'m wondering how executing many long-running queries simultaneously will impact SQL Server\'s ability to service each query in a timely fashion.

[Edit]

Answer 1

obviously, the more queries running, the slower performance will be.

the extent will depend on the data and what kind of queries (updates/deletes/inserts?).

queries that lock tables may be particulary problematic; use of nolock where appropriate may improve performance.